1: Which substance is readily converted from a liquid to a solid by chemical reaction with hydrogen?
cotton-seed oil
glycerin
kerosene
mercury
2: The ability of a substance to remove oxygen from a compound is called
oxidation
hydrogenation
electrolysis
reduction
3: When passed over hot copper oxide, hydrogen acts as
a catalyst
X an oxidizing agent
a reducing agent
a solute
4: Hydrogen can be prepared by reacting cold water with
aluminum
iron
platinum
X sodium
5: The safest way to make hydrogen in the laboratory is to add hydrochloric acid to
calcium
iron
potassium
sodium
6: Hydrogen may be formed when steam reacts with hot
copper
X iron
mercury
silver
7: The lightest element known is
boron
helium
hydrogen
lithium
8: Hydrogen is
less dense than air and inert
very soluble in water and combustible
odorless and a reducing agent
denser than air and tasteless
9: Hydrogen may be obtained by the reaction of hydrochloric acid with
copper
mercury
silver
zinc
10: When copper oxide is heated with hydrogen, which substance is oxidized?
X copper
copper oxide
hydrogen
water
11: Uncombined hydrogen is found in
soda water
acids
hydrogen peroxide
water gas
12: When hydrogen and oxygen are mixed
they explode
they combine forming water slowly.
they form hydrogen peroxide.
they form an explosive mixture.
13: Hydrogen was discovered by
Preistly
Scheele
Lavoisier
Cavendish
14: In the preparation of hydrogen in the laboratory the acid used is added through the
delivery tube
thistle tube
trough
collecting bottle
15: Hydrogen is used:
to support burning
as part of fuel gas
as an explosive
as a cooling agent
16: If lead oxide is heated in a stream of hydrogen, the products will be
lead hydride and oxygen
lead and water
lead oxide and hydrogen
lead oxide and water
17: A cold piece of iron was held over a Bunsen flame. Droplets of water collecting on the cool surface indicated that the fuel contained
carbon
carbon dioxide
carbon monoxide
hydrogen
18: Helium rather than hydrogen is used in dirigibles because
it is lighter than hydrogen
it is insoluble
it is cheaper
it does not burn
19: If an explosion results from placing a burning splint into a bottle of gas, the gas may have been
oxygen
carbon dioxide
hydrogen
nitrogen
20: The removal of oxygen from a compound is called
oxidation
hydrogenation
reduction
filtration
21: Holding a bottle of hydrogen inverted and without a cover plate indicates that hydrogen
is a gas
is heaver than air
is lighter than air
is soluble in water
22: In the process of reduction, whenever one substance is reduced, another is
hydrogenated
oxidized
aerated
condensed
2006-09-26 02:10:53 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
Did u seriously send 22 questions out? Maybe you should have done each one individually. This is SO not worth 2 points. Good luck with that.
2006-09-26 02:21:13 · answer #1 · answered by Anonymous · 0⤊ 1⤋
Not 100% sure - but i'm sure we can't help you totally, you've got to do your own homework!
1. Cotton Seed Oil
2. Reduction
3. Reducing agent
4. Sodium
5. Calcium
6.
7. Hydrogen (MW= 0.0079)
8. Odourless and a reducing agent
9. Zinc
10. Copper
11. Acids
12. form an explosive mixture
13. [Hydrogen gas, H2, was first artificially produced and formally described by Theophrastus Bombastus von Hohenheim (1493–1541)—also known as Paracelsus—via the mixing of metals with strong acids. He was unaware that the flammable gas produced by this chemical reaction was a new chemical element. In 1671, Robert Boyle rediscovered and described the reaction between iron filings and dilute acids, which results in the production of hydrogen gas.[3] In 1766, Henry Cavendish was the first to recognize hydrogen gas as a discrete substance, by identifying the gas from a metal-acid reaction as "flammable", and further finding that the gas produces water when burned in air. Cavendish had stumbled on hydrogen when experimenting with acids and mercury. Although he wrongly assumed that hydrogen was a liberated component of the mercury rather than the acid, he was still able to accurately describe several key properties of hydrogen, including the fact that it produced water when burned. In 1783 Antoine Lavoisier gave the element its name and (with Laplace) reported that pure water is produced by burning hydrogen and oxygen.]
14. Delivery tube
15. Explosive
16. TLead and water, i think.
17. The fuel contained hydrogen.
18. It does not burn (helium is INERT)
19. Hydrogen. If it was CO2 or N2, it would have been extinguished because they do not support combustion. If it was O2, the splint will continue burning.
20. Reduction
21. Lighter than air
22. Oxidized
2006-09-26 02:13:07 · answer #2 · answered by chemistry_freako 3 · 1⤊ 0⤋
2: reduction
3: a reducing agent
5: sodium? (not sure but I think so)
7: hydrogen
12: You get water and I think it's explosive, but not sure. Might also be slow.
13: Lavoisier
18: it does not burn
19: oxygen, assuming there were no other gases in the bottle
20: reduction
21:is lighter than air
22: oxidized
2006-09-26 02:25:39 · answer #3 · answered by Anonymous · 0⤊ 0⤋
You've GOT to be kidding!
You actually want somebody else to do all this homework for you?
Did you miss class that day?
I will tutor you for a fee, as my time is too valuable. I earn over $18.00 an hour professionally, and unless I get the credit for the answers, or at least get sufficient compensation, I am in no position to assist with these questions. I mean, maybe help with 1 or 2 answers, but 22 questions?????
Go talk to your teacher and tell him or her that you need help with the assignment.
Good luck.
2006-09-26 02:17:59 · answer #4 · answered by no1home2day 7 · 0⤊ 1⤋
only this once do all your homework for you? then how will you learn?
2006-09-26 04:00:59 · answer #5 · answered by shiara_blade 6 · 0⤊ 0⤋